On his first overseas tour since he was elected, Prime Minister Shinzo Abe is visiting Vietnam, Thailand and Indonesia, three Southeast Asian nations that are major manufacturing bases and growing markets for Japanese companies as the government seeks to grow its moribund economy.

The region is gaining in importance as manufacturers seek to balance risks from their investments in China, where anti-Japanese riots sparked by tensions over a disputed island in the East China Sea have hammered exports and prompted boycotts of some Japanese products.

While less explosive, tensions between Vietnam and China have also been rising over Beijing's claims over the resource-rich South China Sea, much of which Hanoi says belongs to it.

Hanoi was Abe's first stop on the trip, which ends in Jakarta early Saturday.

In brief statements to the media, neither he nor Vietnam's Prime Minister Nguyen Tan Dung mentioned China, but stressed the importance of their partnership.

"For Japan, Vietnam is an important partner," said Abe, in comments translated from Japanese, to Vietnamese and then to English. "Our countries share the same challenge, with economies that can complement in each other." He vowed to strengthen security and economic cooperation.

Japan is Vietnam's largest foreign investor with the total investment of $29 billion in 1,800 projects. The East Asian economic powerhouse is also Vietnam's largest bilateral donor, providing nearly $20 billion in low-interests loans in the past 20 years for infrastructure projects.

Abe, having a second stint as prime minister after health problems cut short an earlier term in 2006-2007, intends to establish an "Abe doctrine" on the diplomatic front, to match his "Abenomics"-style economic program of stimulus spending meant to help pull Japan out of recession.

His most pressing problem is troubles with China. Tensions between the countries have sharpened since September, when the Japanese central government purchased a group of East China Sea islands controlled by Japan but also claimed by China. Beijing responded furiously to the purchase.

The tiny, uninhabited islands surrounded by rich fishing grounds and suspected undersea mineral resources are known as Diaoyu in China and Senkaku in Japan. China has since dispatched maritime survey boats and warships to the waters almost daily, sometimes entering Japanese waters. Chinese warplanes have recently started flying near Japanese airspace.